CVE-2026-83537: unknown wp express checkout
CVSS: 5.3v3.1MediumDeferred
Published 09-09-2026Last modified 09-09-2026
Vulnerability summary
CVE-2026-83537 is a medium (CVSS 5.3) vulnerability in unknown wp express checkout. EPSS estimates a 0.16% chance of exploitation in the next 30 days, higher than 5.1% of scored vulnerabilities. 1 public exploit is recorded. Fixed in 2.5.0.
CVSS score
5.3/10
010
Medium · v3.1 (CVE.org)EPSS score
0.16%
0%100%
Low · +0.05 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1reference
Timeline
- 09-09-2026PublishedVulnerability first disclosed.
- 09-09-2026Last modifiedVulnerability information updated.
Description
The WP Express Checkout WordPress plugin before 2.5.0 does not verify server-side that a payment was actually completed before marking an order as paid, allowing unauthenticated users to forge a completed order without paying.
CVSS metrics
3 scores · 3 sources · 1 versionMedium 5.3Preferred score · CVE.org (CNA)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:NSourcesAll 3 agree
- NVDNIST5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
- wordfenceSource5.3MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
EPSS trend
Probability
0.16%
Chance of exploitation in the next 30 days
Percentile
5%
Versus all other CVEs
30-day change
+0.05 pp
From 0.11% on 19-09-2026
19-09-202619-10-2026
EPSS score0.16%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
1 foundExploit Reference (wpscan.com)
Maturity: unknown
Weaknesses
CWE · root cause- CWE-345Insufficient Verification of Data AuthenticityThe product does not sufficiently verify the origin or authenticity of data, in a way that causes it to accept invalid data.
- CWE-602Client-Side Enforcement of Server-Side SecurityThe product is composed of a server that relies on the client to implement a mechanism that is intended to protect the server.
Affected systems
Unknown1 product
- wp express checkout< 2.5.0
Wordpress1 product
- wp-express-checkout≤ 2.4.0 (fixed in 2.5.0)
2 vendors · 2 products